What is your "inexpensive" hobby that turned out to be expensive/ you gradually invested lots of money into?

Before you know it, you're spending 44 billion on a social media platform.

Yep, that racks up a bill really fast.

I mean a gram is like 25€ and lasts maybe for a fun night. Doesn't sound exactly cheap.

But it also isn't more expensive than drinking (especially in a bar) and a lot more fun.